Okara cellulose-based multifunctional sponge with wet elastic deformation recovery for antibacterial, hemostatic, and antioxidant properties

In the battlefield and emergencies, uncontrolled hemorrhage remains a primary cause of trauma-related deaths, while hemostatic materials still face technical bottlenecks in achieving multifunctional properties such as hemostasis and antibacterial activity. To address this issue, a multifunctional medical sponge was prepared using okara, a cellulose-rich agricultural by-product. First, Tempo oxidation technique was used to prepare oxidized okara cellulose (TOC). Subsequently, with TOC as a reducing and stabilizing agent, cerium oxide-nanosilver composite (CeO 2 @Ag) was synthesized. Finally, the TOC was crosslinked with N-hydroxyethyl acrylamide and introduced into a composite antibacterial agent (CeO 2 @Ag) to prepare a novel multifunctional sponge (TOC/N/CeO 2 @Ag). Furthermore, the sponges featured excellent porous structure (pore size 30–120 μm) and excellent elasticity (shape recovery 87.8 %) at wet state. The blood clotting index of the sponge was 13.6 %, and its hemostatic properties were significantly better than that of the commercially available PVF sponge (49.2 %). The inhibition rates of sponges for S. aureus and E. coli were 95.3 % and 96.4 %, respectively. Moreover, the composite sponge represented excellent blood, cell compatibility and antioxidant activity. This study can be used in fields such as rapid hemostasis and offers a sustainable and effective strategy for the high-value utilization of agricultural by-products.